ISSN 2074-9414 (Print),
ISSN 2313-1748 (Online)

Volume 48, Issue 2, 2018

4872
Abstract
Ice cream is a product with specific composition and properties that are highly valued by a wide range of consumers. Peculiarities of ice cream composition and production technology make it possible to consider the product as a promising carrier and means of biologically active compounds and useful microorganisms supply. The article reveals morphological, biochemical, physiological, genetic and technological characteristics of L. acidophilus. It systematizes information on the existing methods used for production of ice cream with L. acidophilus. The author shows the influence of various forms of the introduced acidophilus bacteria and methods for their adaptation on ice cream quality indicators. The article provides the data on the properties of ice cream fermented and unfermented with this cultures. It reveals information on the impact of various technological, physicochemical and physiological factors on the survival capacity of pure culture L. acidophilus and its combination with other microorganisms in the process of ice cream production, storage and consumption. The author considers perspective ways of acidophilic ice cream production using various combinations of prebiotics, dietary fibers, replacing refined sugar with honey and unrefined sugars, introducing whey proteins, fruit puree, grain additives and other ingredients. The article presents the data on the influence of functional components on the production process and properties of ice cream containing acidophilus bacteria. The author systematized information on ice cream production using different strains of L. acidophilus and Bifidobacterium spp. replacing cowʼs milk with vegetable analogues. Methods for producing ice cream with L. acidophilus and other starter cultures, including yogurt cultures are described. The review justifies practicability of L. acidophilus application in ice cream production. It reveals trends and issues in the area of functional use ice cream production.
3344
Abstract
Common characteristic of salad products is presence of cut raw vegetables in its composition. Cold cutting helps surface microorganisms penetrate into deep layers of the product. Hygienic cleanliness of raw ingredients is the major factor which contributes to storage stability of salad products. One of the most effective methods that helps enhance salad storage stability is initial treatment of vegetable raw materials with antimicrobial solutions. The author presents information on using solutions of hydrogen peroxide and peroxyacetic acid, sodium hypochlorite and compositions containing peroxide compounds and acetic, benzoic, sorbic, ascorbic, citric, lactic and other acids as well as their salts and containing guanidylic compounds. The article reveals that antimicrobial action of lactate-containing processing aids improves sufficiently if polymer cation-active compounds are introduced into their composition. The goal of the research is to study application effectiveness of new processing aids for treatment of raw peeled cut vegetables to reduce bacterial content and enhance storage stability before thermal treatment (boiling). The author tested the aids based on lactate-containing components. Physicochemical and physical parameters of the aids and their aqueous solutions are the following: active acidity (pH), titratab6le acidity, water and volatiles mass fraction, dynamic viscosity, surface tension. The article presents the data which characterize change in surface tension of aqueous solutions of the aids at the water-air interface depending on their concentration. It also gives quality indicators and microbial parameters of raw peeled cut vegetables after their processing with solutions of the aids. It was found out that treatment of raw peeled cut vegetables with processing aids based on lactate containing components prolongs their shelf life from 3 hours according to the applicable technology up to 48 hours.
4249
Abstract
Narrow range of Russian products for consumers with celiac disease, high prices and low nutritional value of these products determine the relevance of the development of new flour confectionery products for consumers who stick to a gluten-free diet. The aim of the work was to develop a food concentrate – semi-finished product for gluten-free cupcakes cooking. The main object of the studies was flour obtained from amaranth seeds which had been chosen because of the advantages of its chemical composition compared to the traditional industrial types of gluten-free flour – rice flour and corn flour. Amaranth flour was introduced into the dough in the form of a homogeneous mixture with corn flour or rice flour. It amounted for 5.0% to 25.0% of the total amount of flour. According to the results of studies of organoleptic and physicochemical indicators of the cupcakes quality the authors proposed the optimal combinations of corn flour and amaranth flour; rice flour and amaranth flour. They showed that if the dough base includes corn flour and amaranth flour in the ratio of 10.0–12.5% : 90.0–87.5% or rice flour and amaranth flour in the ratio of 15.0–17.5% : 85.0–82.5% it allows to obtain standard quality cupcakes. Considering these data the authors developed the recipes of semi-finished gluten-free cupcakes with amaranth flour. Calculation of nutritional value of semi-finished gluten-free cupcakes cooked following the developed recipes showed that corn-amaranth and rice-amaranth cupcakes had a better ratio of basic nutrients. They had higher content of easy-to-digest gluten-free proteins (up to 7.9–8.4 g/100 g of semi-finished product) and dietary fibers (up to 1.2–3.4 g/100 g of semi-finished product). They had lower total fat content (4–5 times). Based on the results of the conducted research it is possible to confirm that the use of amaranth flour in the development of semi-finished gluten-free cupcakes can significantly increase the nutritional value of these products and to extend the product range of affordable gluten-free Russian products.
3626
Abstract
Modern trends which imply maximum using of all caryopsis anatomical parts in people’s diet present a great interest from the point of view of developing a ready-to-eat preserved food “Second Course for Lunch” based on prepared whole grain in a convenient polymer package. The author suggested using the method of preparing wheat grain by means of steeping, parboiling, and adding it in the preserved food as one of the recipe ingredients. The subject of the study was hulless wheat grain harvested in the Republic of Belarus. The author studied grain quality parameters using standard procedures, grain preparation stages, changes in microbial flora during preparation. Besides, parboiling parameters of the prepared grain were determined. Swelling ratio was determined (k = 1.3) for wheat grain steeping in water at 18 ± 2 °C during 30 hours with water changes every 5 hours till humidity reached 44.4 ± 1 %. Seed vigor (92.0–96.2 %) and swelling ratio (k = 1.3) are considered during calculation of raw material usage rate in the production of preserved food. It was determined that during steeping bacterial content rises sufficiently, and that process takes place when steeping period increases. The author optimized the process of sprouted grain parboiling and determined parboiling technological parameters: at 95–98 °C for 20 min. The process of salt solution absorption by grain after processing during storage of preserved food model samples was considered. The author found out that absorption stops after 60 days of storage. Grain swelling ratio is k = 1.12.
3072
Abstract
The article is devoted to the analysis of modern priorities in the sphere of food industry main branches development. The author identified the most promising of them, in particular, modification of socially significant food products (fats) by means of their combination with traditional and non-traditional plant raw materials having full fat oil and low-oil content as a source of physiologically functional nutrients. Chemical composition of raw materials has been studied to reveal the biological value and food safety. The efficiency of using wheat germ flour as an ingredient of vegetable fatty composite mixtures in bread production is established. The author suggested using composites that consist of germinated wheat product, animal fat, creamy melted butter, palm, soybean and sunflower oils which have balanced fatty acids content. The author justified the relevance of heat treatment of composite mixtures having wheat germ flour content up to 30.0% of the mixture mass at 40–50 °C, more than 30% – up to 70°C during 10–15 min. That will help increase its microbiological purity, reduce the enzymatic action of germ lipase, protease and lipoxygenase, extend the mixtures shelf life up to 45 days. Optimum proportion of wheat germ flour should not exceed 70.0% of the raw material mixtures weight. It was demonstrated that 30,0 to 50,0% of solid fats can be replaced with vegetable oils. There was a positive effect of the developed composites in the amount of up to 5.0% to the quantity of flour according to the recipe on the quality of bread produced from the 1st grade wheat flour.
3348
Abstract
Different grain raw materials are used to enrich products. Wheat juice is a source of nutrients, vitamins, macro- and microelements, enzymes, amino acids, including irreplaceable ones. Green sprouts of wheat grain were taken as a research object. The juice pressing was made using juice extractors with various operating principles. Organoleptic, physicochemical and microbiological properties of wheat sprouts juice were determined. Wheat sprouts juice was packed into vacuum packages and packages for ice, intensively cooled and frozen respectively to prevent the product from spoilage during storage. Quality control was carried out considering three control points during 10 days of storage. Organoleptic and microbiological indicators of wheat sprouts juice were determined in these points. The author developed a production technology of juice obtained from wheat sprouts which germinated in a steam convection apparatus up to 10cm length. Screw juice extractor and intensive cooling machine were used. The author determined storage modes and periods: in vacuum packing at humidity of 75%, 4±2 °C it can be stored for 5 days; in packages for ice at humidity of 75%, −18±2 °C – for 7 days. Consumption of 100g of wheat sprouts juice satisfies daily nutrient requirement for sugar – 1.5–1.74%, vitamin C – 5.6%, B2 – 38.8%, B9 – 20%, K – 6.3%, in calcium – 0.8%, iron – 2.8–5.1%, magnesium – 0.75%, potassium – 20.1%, sodium – 0.38%. That demonstrates high nutritional value of a product.
3538
Abstract
Production of functional foods containing such functional ingredients as pectin and anthocyanins is particularly important nowadays. The goal of the given research was to study the effect of high esterified pectin obtained from apples at a dosage of 0.3% on the changes of viscosity and color of drinks based on cherry juice and anthocyanin colourant obtained from black carrot, apple juice and sugar color IV during storage in a dark place at 22 ± 3 °C for 180 days. Optical density was measured using spectrophotometric method at a wavelength of 350 to 700 nm. Mass fraction of solid matter was adjusted using sucrose to reach 10.1 ± 0.7 %, pH for drinks based on cherry juice and anthocyanin colourant obtained from black carrot was adjusted to reach 3.0, and for drinks based on apple juice and sugar color IV – to reach 3.5 in the prepared beverages. The author shows that pectin does not have any significant effect on colour retention in drinks based on cherry juice and anthocyanin obtained from black carrot, and that anthocyanin colourant from black carrots is more stable during storage than the colourant that cherry juice contains. The color of the drinks based on apple juice and sugar color IV without pectin remains almost the same during storage. In the visible spectrum region they have a monotonous graph of the change in optical density, and pectin makes a significant contribution to the final color. It is established that for 180 days of storage kinematic viscosity of the beverages with pectin decreased not more than 12%, that indicates a high level of pectin preservation. According to the results of the research, the author makes a conclusion that the use of pectin to preserve the color of beverages with natural colourants is not practical. It makes sense to use pectin in order to give the beverages functional properties, as well as to increase their viscosity and stability.
2972
Abstract
Development of new types of functional whipped confectionery of souffle type in which animal proteins are replaced with vegetable ones is promising and of high priority. The author proposed to introduce top grade wheat flour into the recipe of the whipped product and lemon zest as an enriching additive. Experimental studies were carried out under laboratory conditions of the department of technology of bakery, confectionery, macaroni and grain processing industries of Voronezh State University of Engineering Technologies. The whipped product was obtained using an experimental whipping device developed by the staff of the department. The author justified the choice of the components in the recipe. The optimum modes of obtaining the whipped product which includes top grade wheat flour, water, citric acid, agar, white sugar, molasses, and lemon zest were selected using the experimental-statistical approach. The main cooking parameters are the duration of whipping (seconds); rotation frequency of the whipping parts (minutes-1), an output parameter (the volume weight of the final product, g/cm3). The results are the following: duration of the mass whipping x1 = 379 s-1, rotation speed of the whipping parts x2 = 651 min-1. The author determined quality indicators of the final whipped product. It has a good form-retaining ability, uniform and fine-porous structure, slightly creamy color, and slight taste of lemon zest. Mass fraction of dry matter is 76%, density – 0.43 g/cm3. The obtained product has original organoleptic parameters and higher nutritional value. The author did not include any food color additives and flavoring agents. For that reason the product can be recommended not only to people suffering from egg white intolerance, but also to all categories of consumers.
3702
Abstract
Sour ales have become widely spread in Europe since XVII century. These drinks are still popular in Germany, Belgium, England and other European countries. Interest in sour ales has been growing steadily in Russia. The purpose of this work was to systematize and generalize scientific data and the results of practical use of lactic acid bacteria of the genus Lactobacillus in sour ales production technology and in the formation of the ready beverage flavor profile. The subjects of the research were biochemical and biotechnological properties of lactic acid bacteria of the genus Lactobacillus frequently used in sour ales production, namely, L. delbrueckii, L. brevis, L. buchneri, L. fermentum, L. plantarum. The results of studying sour ales composition by means of gas chromatography, solid phase microextraction, liquid chromatography, and mass spectroscopy show that they have complex compositions. Thus, sour ales of Lambic and Gueuze groups have 64 volatile compounds. Taste and aroma of sour ales are mostly formed by the most important components synthesized during lactic-acid fermentation. They are higher alcohols, complex esters, organic acids, dimethyl sulfide and diacetyl. Concentration of these components is mainly determined by the type of lactic acid bacteria. The article generalizes and systematizes scientific data concerning biochemical and biotechnological properties of different types of lactic acid bacteria of the genus Lactobacillus used for sour ale production. The article reveals concentrations of the main products and by-products synthesized by the given types of lactic acid bacteria during fermentation. The author points out corresponding taste and aroma sensations according to terminology used in European Brewing Convention (EBC).
3765
Abstract
The work reveals the results of the study devoted to milk ice cream composition improvement in order to meet the requirements for healthy foods (with satisfactory nutritional value) to the fullest extent and to obtain creamy consistency as well as high dispersity of structural elements typical for products with high mass fractions of fat and dry substances. The significance of the research is determined by the worldwide trend in the production of healthy foods which is developed in our country by a number of legislative documents. The purpose of the research was to develop on the basis of the composition a milk ice cream product with low energy value and high organoleptic parameters including the state of its structure. Within the framework of the given research the author used such modern research methods as rheological, microstructural and thermostating ones as well as photographic survey method. The author justified analytically and experimentally the use of such food additive as polydextrose having low energy value. It increases the feeling that food product has high fat content and it does not have any negative effect on ice cream production process. The possibility of improving the product structure using synergistic compositions such as emulsifiers based on distilled monoglycerides and polyglycerol and fatty acids esters as well as stabilizers containing mainly locust bean gum which promotes the formation of small ice crystals was confirmed experimentally. The mentioned compositions of emulsifiers and stabilizers when used with polydextrose made it possible to achieve technologically significant results in milk ice cream production. They increased the effective viscosity of the mixtures, provided high form and thermal stability, and made it possible to get high dispersion of ice crystals. The accepted technological solutions had positive effect on the consistency and structure of milk ice cream with improved composition.
3099
Abstract
The development of scientific bases for isolation of whey components in food enterprises by means of flocculants is an urgent task that makes it possible to solve environmental issues and utilize valuable products (proteins, fat, lactose) that whey contains. The goal of the given work was to study the modified flocculant properties such as swelling and light absorption which have an effect on the completeness of components isolation from milk whey. The research objects of the scientific work were the following: flocculants based on polyacrylamide: Magnafloc 156, Magnaflok 24 and Magnaflok 919; modifiers: propylene glycol, ethylenechlorhydrin, propylene chlorohydrin, amino acids serine and glycine, and whey. The study took place in Kemerovo region. The obtained data reveal that though the swelling degree has approximately the same values, the swelling time of the original and modified flocculants decreases starting with Magnafloc 24 and up to Magnafloc 919. Magnafloc 156, a medium anionic polyelectrolyte with an average degree of macromolecule expansion, is the most optimal among them concerning the swelling rate. The author proved that as a result of modification the flocculants molecular weight increases 1.4–2.4 times. It is established that the average distance between the ends of macromolecules increases 1.3–1.8 times; there is a slight decrease in flexibility; hydrodynamic volume increases 1.33–9.9 times. The author experimentally established that the absorption peaks for the modified flocculants in the ultraviolet region shift to a longer wavelength region compared to the original polyelectrolytes. That indicates that due to the modification process large particle aggregates have been formed. Based on the experiment, the following technological parameters were obtained for milk whey components isolation: flocculant concentration – 0.05%; amount of flocculant – 6 g/m3; temperature – 25–30°C; flocculation time – 10–20 min; feeding method – continuous; settling time – 60 min; angular speed of stirring – 30–40 rpm. The author offered a technological scheme for whey components isolation. It is proved that modified flocculants isolate valuable components from whey much better than unmodified ones.
3158
Abstract
Nowadays there is a significant engineering and technical issue which is corrosion of structural materials, metal equipment and installations. Inhibitors are one of the effective, universal and economical means of protection against corrosion. The author justifies the relevance of the problem connected with selection of corrosion inhibitors for food industry companies. The aim of the work is to study the effect of inhibitors based on plant raw materials on increasing the corrosion resistance of food industry equipment in technological corrosive media. A literature review showed that the use of synergistic inhibitory compositions is more effective than using inhibiting additives separately. A specified inhibitor is a modified plant raw material. It has biocidal and bactericidal properties that provide for high efficiency of corrosion protection of structural steels in neutral and acid media and is used to improve protective and physico-mechanical properties of coatings. The author studied the effect of concentrate inhibitor in the working environment on the basis of technological regulations to justify recommendations on the use of this concentrate in protecting equipment against corrosion. As a result of the study, the author determined that the greatest effect took place when a modified concentrate inhibitor was used. The plant-based concentrate inhibitor does not have lower corrosion protection effectiveness than the industrial inhibitor PB-5. On the contrary, it has a number of definite advantages such as environmental safety, multiple action directions as well as a positive effect on the sanitary and hygienic conditions in the process of inhibitor preparation and use. The author gives recommendations on the possibility of using this inhibitor to protect the mechanisms used in food industry against corrosion.
3382
Abstract
The article presents the results of research on the peculiarities of proofing and baking bakery products using a steam-convection oven for continuous proofing and baking. The aim of the work was to develop recommendations for setting parameters for production of bakery products in the steam-convection oven at continuous proofing of dough pieces and bakery products. For control samples baking the author used a proofing box for final proofing and a convection oven. The analysis of the structural and mechanical properties of crumb was made using device “Strukturometer-1”, and loss of weight after baking was measured using standard methods. Intensity and color uniformity of crust were determined applying an ingenious method using flatbed scanner. Automatic recorder monitored the temperature in the baking chamber and inside the baked dough pieces. To determine the changes in product volume and proportion of the formed crumb during baking process, an original optical method was used. As a result of the research the author determined that there is a dependence of the dynamics of baked dough pieces quality indicators on proofing and baking parameters. It is shown that the main differences are observed during the first baking period. The detected regularities are associated with smooth heating of the steam-convection oven baking chamber and high relative humidity of the medium at the beginning of baking process. When using a steam-convection oven, the crusts had uneven color which is obviously due to condensation of a large amount of moisture on the surface during the initial baking period and, consequently, different rates of heating of individual parts of the crust. By the moment when baking process was over control samples and developed samples had insufficient differences concerning structural, mechanical and physicochemical parameters. It was determined that in case of continuous proofing and baking in steam-convection oven it is necessary to extend the baking process and increase dough humidity compared to traditional baking method.
3070
Abstract
Clinical tests were carried out in the representative group of patients with focal left-sided pneumonia (5 men and 7 women aged 18–41). Special-use product was included in in-patient department patients’ diet: 2 tablets in the first intake, then 1 tablet 4 times a day. Course of treatment was 21 days. Biologically active dietary supplement was prescribed together with general therapeutic treatment according to generally accepted standards of care. Control group included 15 patients randomized depending on sex and age who took only medicine. The author measured body temperature, studied the results of general blood tests, determined the level of C-reactive protein and seromucoids, performed R-graphy of lungs, electrocardiogram before and after treatment, analyzed clinical symptoms (cough, type of expectoration, shortness of breath). Composition of the special-use product was scientifically justified taking pharmacological characteristics of its ingredients and their active agents into account. Introduction of the biologically active dietary supplement in addition to the prescribed therapeutic treatment gave positive effect in relation to the inflammatory process: the patients could easier clear their throats from expectoration, coughed less frequently, and had less intense shortness of breath. It was evident that symptoms of disease recrudescence decreased. It appeared in the decreased intensity and length of fever. In case of acute respiratory viral infection the biologically active dietary supplement had antipyretic activity due to the anti-exudative effect of its ingredients. The author determined the anti-inflammatory effect and reduction of acute intoxication symptoms taking the results of general blood analysis into account. Patients who took special-use product had lower values of an inflammatory process marker – seromucoids. Tissues restored easily. The tested product has anti-inflammatory, antipyretic and analgesic properties. It can be used in complex treatment of acute inflammatory diseases and recrudescence of chronic inflammatory processes.
3987
Abstract
The relevance of research is the experimental and analytical justification of the effectiveness of the joint use of biopolymers of animal and plant origin as a substrate in the process of immobilization of the association of probiotic cultures. Researches are executed in specialized laboratories of universities: Omsk GAU, Saratov GAU, SKFU. In the form of a substrate were used: gelatin, χ-carrageenan, low-esterified pectin, modified starch; as bioobjects are selected: L. acidophilus, B. Lactis, S. thermophilus. To obtain reliable and complete characteristics, a set of research methods was used in the work: physicochemical, sensory, and microbiological. Investigation of immobilization allowed to determine the optimal ratio of biopolymers as a carrier (substrate): pectin and gelatin, as 2:1; the total concentration of solids of the carrier solution (20.0 ± 0.5)% by weight. The total number of viable cells of probiotic microorganisms in membranes (plates) is an average of lg (11.0 ± 0.55). In order to extend the shelf life, the membranes were dried in a freeze dryer, with parameters: the temperature of the frozen product (–25 °C) and the residual pressure in the sublimate 0.013–0.133 kPa. Immobilization by microencapsulation of the association of probiotic cultures of L. acidophilus, B. Lactis and S. thermophilus into a gel of biopolymers: gelatin food, pectin gene LM 106 AS-YA, starch in a ratio of 5:1:1 was studied by microencapsulation. The obtained microcapsules were studied in imitated gastric and intestinal conditions, while the number of viable probiotic cells was determined at different times of their degradation. It was established that 20–25% of viable cells of probiotics were released from capsules in the "artificial stomach" phase, 75–80% in the "artificial bowel" phase. Innovative biotechnologies of milk based products for specialized nutrition are presented.
3456
Abstract
Resent scientific works demonstrate that population physical health depends on food quality. One of the important modern problems is lack of biologically active substances such as vitamins, antioxidants, and mineral substances in food. Many of them cannot be synthesized by the human body and must come with food. Tomato paste can be the source of the antioxidants necessary for the human body. The purpose of this work was to determine the content of carotenoids in tomato paste samples. Tomato paste contains a significant amount of carotenoids, mainly β-carotene and lycopene. As a result of experimental studies, the author determined the content of carotenoids, β-carotene and lycopene in tomato paste samples produced in Russia and abroad. It was found out that there is a direct proportion between the content of carotenoids and β-carotene: the higher the content of carotenoids, the higher the content of β-carotene. Proportion of β-carotene in all studied samples is a little more than 12% of the total amount of carotenoids. Consumption of concentrated tomato products by different age and social population groups in Russia will help improve food ration by means of providing β-carotene and lycopene according to the physiological requirements in nutrients
3064
Abstract
To reduce the accumulation of toxic substances in tubers in 2014–2016 the author studied biological methods of fertilizers application and plant protection in black earth forest-steppe region under the conditions of high-intensity potato cultivation technology along with drip irrigation. The introduction describes the importance of potato in the diet of population and lists the environmental issues that arise as a result of enhanced using of chemicals during crop cultivation. The doses of mineral fertilizers in experiments were introduced separately and in combination with a bioameliorant: 1) without fertilizers (control site); 2) N60P90K60; 3) N90P135K90; 4) N120P180K120; 5) biological ameliorant – white mustard, post-harvest green manure; 6) bioameliorant + N60P90K60; 7) bioameliorant + N90P135K90; 8) bioameliorant + N120P180K120. Chemical insecticide Aktara and biological preparations Fitoverm, Akarin were used to protect potatoes against Colorado potato beetles. Insecto-fungicide Celest was used to treat seed tubers against fungal diseases. During growing season the author used fungicides Profit Gold, Ridomil Gold against fungal diseases, against weeds – Zenkor and Remus. High yield of potato environmentally friendly considering nitrates was obtained by means of simultaneous application of N90P135K90 and white mustard green mass. Tuber yield was 40.4 tonnes per hectare compared to 22.7 tonnes per hectare on the control site, and nitrate content was 111.3 mg while maximum permissible concentration (MPC) is 250 mg/kg. According to MPC established in the Russian Federation, for childrenʼs and dietary nutrition fertilizer dose should not exceed N60P90K60 in combination with a bioameliorant and a biological plant protection system. Safety interval (period between plant treatment and harvesting) for chemical insecticides is 35–40 days; fungicides – 20 days; herbicides (depending on their type) – 55–70 days. The production of ecologically clean potato according to EU standards was achieved only by means of using post-harvest green manure as a fertilizer, applying biological insecticides and Celest preparation within the framework of protecting plants against pests and diseases.
2685
Abstract
Financial policy of any entity comes down to managing economic parameters and relies on exploration of the strength of relations and dependencies between them. By means of analysis of the given indicators and identification of the degree of their correlation with the basic indicators, financial engineers get vast opportunities concerning economic processes modeling and optimization. Thus, in the sector of commercial credit, which is characterized by the absence of complete Russian procedures that would help assess the risk of the creditor, the study of credit analysis exhibitors system provides the key to the development of modern models and methodological assessment technologies. The present scientific work includes theoretical, methodological, analytical and financial engineering components. The theoretical part has to provide the theoretical basis for the research, reflect the terms and definitions overview and show the development of the basic complex concept – algorithmic modeling of commercial debtor segmentation. The methodological component is devoted to the study of the fundamental principles which help construct the system of analytical indicators and establish their connection with the algorithmic model. The analytical and financial-engineering component of the scientific work which is of fundamental importance (as it reflects the implementation of the research focus), consists of five stages: 1) identification and thematic grouping of the creditor's risk indicators; 2) indicators unification in the form of the commercial debtor segmentation algorithm; 3) algorithmic model testing and performance evaluation; 4) explanation of cause-effect relationships strength between the interpenetrating exponents of the algorithmic model; 5) identification of the most valuable parameters (identifying factors) of credit analysis in the commercial lending sector. Studies were carried out using selected materials taken from Kemerovo Region agricultural companies. Thus, the result of the research is the author's debtor segmentation. The model makes it possible to form risk groups in the commercial lending sector. The analytical structure is based on the combination of key credit risk parameters taking regional and industry specific features of businesses operation into account and justified by strong correlation of the algorithm elements. That helps financial analysts save time and have equivalent effect of credit risk assessment procedure.
3030
Abstract
Oxygen is necessary for yeast to synthesize membrane components (unsaturated fatty acids and sterols), but its high content in the medium during fermentation increases the concentration of cell oxidative metabolism products. This slows down beer maturation process and impairs its quality. The alternative way is to aerate the inoculum to accumulate sterols in cells and reduce the cells’ requirement for oxygen. The author studied the effect of inoculum preparation conditions and oxygen content in the fermentation medium on the formation of sterols by the brewer’s yeast Saccharomyces cerevisiae. Pre-fermentation treatment involved a short aeration of the inoculum (for 30 min) in water, beer wort or young beer with further exposure in an anaerobic environment (for 1–3 hours). The content of sterols was evaluated by means of spectrophotometry, chromatography-mass spectrometry, thin-layer chromatography (TLC), and gas-liquid chromatography (GLC). The article reveals that when yeasts are aerated in young beer, cells synthesize by 16% and 73% more sterols than in water and wort, respectively. This is due to the presence of carbon sources in beer which are effective for sterols synthesis. After application of any method for providing yeast with oxygen (at culture preparation or wort fermentation stage) six components were detected in the unsaponifiable fraction using TLC: ergosterol, ergosta-5,7-diene-3β-ol, ergosta-7,22-diene-3β-ol, fecosterol, zymosterol, lanosterol. GLC revealed five compounds: squalene (39–54%), lanosterol, 24 (28) -dihydroergosterol, ergosterol (23–35%) and an unidentified component which according to mass spectrometry was 24-methylene-24,25-dihydrolanosterol. An increase in the oxygen level in the fermentation medium from 4.0 to 16.0 mg/l contributes to the decrease in sterols accumulation per unit of oxygen consumed by the yeast. Preliminary aerationallowed yeast to multiply regularly at oxygen concentration in the fermentable wort of 4.0 mg/l and ferment the extract of the medium at the level of the sample where oxygen content was 8.0 mg/l. This shows the advantage of using yeast pre-fermentation aeration and conducting beer wort fermentation process without additional saturation with oxygen.